Development and Validation of Stability-Indicating RP-HPLC Method for Determination of Atazanavir and Ritonavir

A new simple, accurate, precise and selective stabilityindicating high performance liquid chromatographic (HPLC) method has been developed and validated for simultaneous estimation of Atazanavir and Ritonavir in tablet dosage form. An isocratic, reverse phase HPLC method was developed on Jasco HPLC system equipped with Grace C₁₈ column (150 x 4.6 mm i.d.) using 10 mM Potassium dihydrogen phosphate buffer: Acetonitrile: Methanol (40: 40: 20, v/v/v) as mobile phase and detection was carried out at 240 nm. Results were linear in the range of 50500 μg mL¹ for Atazanavir and 25400 μg mL¹ for Ritonavir. The retention time for Atazanavir and Ritonavir were 5.54 ± 0.02 and 6.82 ± 0.07 min. respectively. The drugs were subjected to stress condition of hydrolysis (acid, base), oxidation, photolysis and thermal degradation.